/*
 * Copyright (c) 1997-2010 Oracle and/or its affiliates. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 *   - Neither the name of Oracle nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */



//~--- JDK imports ------------------------------------------------------------

import java.io.*;

/**
 * Convert lines into the canonical MIME format, that is,
 * terminate lines with CRLF. <p>
 *
 * This stream can be used with the Part.writeTo and Message.writeTo
 * methods to generate the canonical MIME format of the data for the
 * purpose of (e.g.) sending it via SMTP or computing a digital
 * signature.
 */
public class CRLFOutputStream extends FilterOutputStream {
    protected static byte[] newline;

    static {
        newline    = new byte[2];
        newline[0] = (byte) '\r';
        newline[1] = (byte) '\n';
    }

    protected int lastb = -1;

    public CRLFOutputStream(OutputStream os) {
        super(os);
    }

    public void write(int b) throws IOException {
        if (b == '\r') {
            out.write(newline);
        } else if (b == '\n') {
            if (lastb != '\r') {
                out.write(newline);
            }
        } else {
            out.write(b);
        }

        lastb = b;
    }

    public void write(byte b[]) throws IOException {
        write(b, 0, b.length);
    }

    public void write(byte b[], int off, int len) throws IOException {
        int start = off;

        len += off;

        for (int i = start; i < len; i++) {
            if (b[i] == '\r') {
                out.write(b, start, i - start);
                out.write(newline);
                start = i + 1;
            } else if (b[i] == '\n') {
                if (lastb != '\r') {
                    out.write(b, start, i - start);
                    out.write(newline);
                }

                start = i + 1;
            }

            lastb = b[i];
        }

        if ((len - start) > 0) {
            out.write(b, start, len - start);
        }
    }
}


//~ Formatted by Jindent --- http://www.jindent.com
